Various liquid agents are routinely administered to one or both eyes of a human via eyedrops for a variety of reasons. Examples of these agents include medicaments, moisturizers, irrigators, dilators, and anesthetics, among others. Some of these agents are typically self-administered, i.e., administered by the person receiving the agent, and others of these agents are typically administered by a health care professional. Regardless of who administers the agents, the administration is commonly accomplished using a squeeze bottle type applicator having a generally frusto-conical applicator tip.
To administer an agent to an eye using such an eyedrop applicator, the person receiving the eyedrop typically must tilt his/her head backward or be in a supine or otherwise reclined position. These are often awkward positions for the person, particularly if the person is self-administering the eyedrop. In addition, when the person is self-administering the eyedrop, he/she often has difficulty positioning the applicator over the eye so that the eyedrop is administered to the proper location. While in one of these awkward positions, it is also difficult for the person to determine how large the droplet, or portion thereof, is that actually reaches the eye. Thus, the person does not know whether or not he/she has administered the agent in the proper amount. Complicating this uncertainty in knowing how much of the agent reached the eye due to not being able to position the applicator properly is the fact that most commercially available eyedrop applicators do not have any precise means for metering the size of each eyedrop, thereby controlling the amount of agent dispensed.
Another drawback of most conventional squeeze-type eyedrop applicators is that some users have difficulty controlling the amount of pressure they use when squeezing the container and often dispense far more of the agent than is necessary. This can result in much waste of the agent, which, depending on the particular agent, can be expensive. Some elderly people and others having diminished fine motor control are the groups of people that appear to have the most difficulty in controlling the amount of agent dispensed. Often, these groups are among those least likely to be able to afford such waste and among those most likely to self-administer eyedrop agents.